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            <div><h4 class="title">
                <a name="asio.overview.networking.other_protocols"></a><a class="link" href="other_protocols.html"
                                                                          title="Support for Other Protocols">Support
                for
                Other Protocols</a>
            </h4></div>
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    <p>
        Support for other socket protocols (such as Bluetooth or IRCOMM sockets)
        can be added by implementing the <a class="link" href="../../reference/Protocol.html"
                                            title="Protocol requirements">protocol
        type requirements</a>. However, in many cases these protocols may also
        be used with Asio's generic protocol support. For this, Asio provides the
        following four classes:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                <a class="link" href="../../reference/generic__datagram_protocol.html"
                   title="generic::datagram_protocol"><code class="computeroutput"><span
                        class="identifier">generic</span><span class="special">::</span><span class="identifier">datagram_protocol</span></code></a>
            </li>
            <li class="listitem">
                <a class="link" href="../../reference/generic__raw_protocol.html" title="generic::raw_protocol"><code
                        class="computeroutput"><span class="identifier">generic</span><span
                        class="special">::</span><span class="identifier">raw_protocol</span></code></a>
            </li>
            <li class="listitem">
                <a class="link" href="../../reference/generic__seq_packet_protocol.html"
                   title="generic::seq_packet_protocol"><code class="computeroutput"><span
                        class="identifier">generic</span><span class="special">::</span><span class="identifier">seq_packet_protocol</span></code></a>
            </li>
            <li class="listitem">
                <a class="link" href="../../reference/generic__stream_protocol.html"
                   title="generic::stream_protocol"><code class="computeroutput"><span class="identifier">generic</span><span
                        class="special">::</span><span class="identifier">stream_protocol</span></code></a>
            </li>
        </ul>
    </div>
    <p>
        These classes implement the <a class="link" href="../../reference/Protocol.html" title="Protocol requirements">protocol
        type requirements</a>, but allow the user to specify the address family
        (e.g. <code class="computeroutput"><span class="identifier">AF_INET</span></code>) and protocol
        type (e.g. <code class="computeroutput"><span class="identifier">IPPROTO_TCP</span></code>)
        at runtime. For example:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">generic</span><span class="special">::</span><span
            class="identifier">stream_protocol</span><span class="special">::</span><span
            class="identifier">socket</span> <span class="identifier">my_socket</span><span
            class="special">(</span><span class="identifier">my_io_context</span><span class="special">);</span>
<span class="identifier">my_socket</span><span class="special">.</span><span class="identifier">open</span><span
                class="special">(</span><span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">generic</span><span class="special">::</span><span
                class="identifier">stream_protocol</span><span class="special">(</span><span
                class="identifier">AF_INET</span><span class="special">,</span> <span
                class="identifier">IPPROTO_TCP</span><span class="special">));</span>
<span class="special">...</span>
</pre>
    <p>
        An endpoint class template, <a class="link" href="../../reference/generic__basic_endpoint.html"
                                       title="generic::basic_endpoint"><code class="computeroutput"><span
            class="identifier">asio</span><span class="special">::</span><span class="identifier">generic</span><span
            class="special">::</span><span class="identifier">basic_endpoint</span></code></a>, is included to
        support these protocol classes. This endpoint can hold any other endpoint
        type, provided its native representation fits into a <code class="computeroutput"><span class="identifier">sockaddr_storage</span></code>
        object. This class will also convert from other types that implement the
        <a class="link" href="../../reference/Endpoint.html" title="Endpoint requirements">endpoint</a> type
        requirements:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span><span
            class="special">::</span><span class="identifier">endpoint</span> <span
            class="identifier">my_endpoint1</span> <span class="special">=</span> <span class="special">...;</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">generic</span><span
                class="special">::</span><span class="identifier">stream_protocol</span><span
                class="special">::</span><span class="identifier">endpoint</span> <span
                class="identifier">my_endpoint2</span><span class="special">(</span><span class="identifier">my_endpoint1</span><span
                class="special">);</span>
</pre>
    <p>
        The conversion is implicit, so as to support the following use cases:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">generic</span><span class="special">::</span><span
            class="identifier">stream_protocol</span><span class="special">::</span><span
            class="identifier">socket</span> <span class="identifier">my_socket</span><span
            class="special">(</span><span class="identifier">my_io_context</span><span class="special">);</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">endpoint</span> <span class="identifier">my_endpoint</span> <span
                class="special">=</span> <span class="special">...;</span>
<span class="identifier">my_socket</span><span class="special">.</span><span class="identifier">connect</span><span
                class="special">(</span><span class="identifier">my_endpoint</span><span class="special">);</span>
</pre>
    <h6>
        <a name="asio.overview.networking.other_protocols.h0"></a>
        <span><a name="asio.overview.networking.other_protocols.c__11_move_construction"></a></span><a class="link"
                                                                                                       href="other_protocols.html#asio.overview.networking.other_protocols.c__11_move_construction">C++11
        Move Construction</a>
    </h6>
    <p>
        When using C++11, it is possible to perform move construction from a socket
        (or acceptor) object to convert to the more generic protocol's socket (or
        acceptor) type. If the protocol conversion is valid:
    </p>
    <pre class="programlisting"><span class="identifier">Protocol1</span> <span class="identifier">p1</span> <span
            class="special">=</span> <span class="special">...;</span>
<span class="identifier">Protocol2</span> <span class="identifier">p2</span><span class="special">(</span><span
                class="identifier">p1</span><span class="special">);</span>
</pre>
    <p>
        then the corresponding socket conversion is allowed:
    </p>
    <pre class="programlisting"><span class="identifier">Protocol1</span><span class="special">::</span><span
            class="identifier">socket</span> <span class="identifier">my_socket1</span><span
            class="special">(</span><span class="identifier">my_io_context</span><span class="special">);</span>
<span class="special">...</span>
<span class="identifier">Protocol2</span><span class="special">::</span><span class="identifier">socket</span> <span
                class="identifier">my_socket2</span><span class="special">(</span><span
                class="identifier">std</span><span class="special">::</span><span class="identifier">move</span><span
                class="special">(</span><span class="identifier">my_socket1</span><span class="special">));</span>
</pre>
    <p>
        For example, one possible conversion is from a TCP socket to a generic
        stream-oriented socket:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span><span
            class="special">::</span><span class="identifier">socket</span> <span
            class="identifier">my_socket1</span><span class="special">(</span><span
            class="identifier">my_io_context</span><span class="special">);</span>
<span class="special">...</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">generic</span><span
                class="special">::</span><span class="identifier">stream_protocol</span><span
                class="special">::</span><span class="identifier">socket</span> <span
                class="identifier">my_socket2</span><span class="special">(</span><span
                class="identifier">std</span><span class="special">::</span><span class="identifier">move</span><span
                class="special">(</span><span class="identifier">my_socket1</span><span class="special">));</span>
</pre>
    <p>
        These conversions are also available for move-assignment.
    </p>
    <p>
        These conversions are not limited to the above generic protocol classes.
        User-defined protocols may take advantage of this feature by similarly
        ensuring the conversion from <code class="computeroutput"><span class="identifier">Protocol1</span></code>
        to <code class="computeroutput"><span class="identifier">Protocol2</span></code> is valid,
        as above.
    </p>
    <h6>
        <a name="asio.overview.networking.other_protocols.h1"></a>
        <span><a name="asio.overview.networking.other_protocols.accepting_generic_sockets"></a></span><a class="link"
                                                                                                         href="other_protocols.html#asio.overview.networking.other_protocols.accepting_generic_sockets">Accepting
        Generic Sockets</a>
    </h6>
    <p>
        As a convenience, a socket acceptor's <code class="computeroutput"><span class="identifier">accept</span><span
            class="special">()</span></code> and <code class="computeroutput"><span
            class="identifier">async_accept</span><span class="special">()</span></code> functions can directly accept
        into a
        different protocol's socket type, provided the corresponding protocol conversion
        is valid. For example, the following is supported because the protocol
        <code class="computeroutput"><span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span></code> is
        convertible to <code class="computeroutput"><span class="identifier">asio</span><span
            class="special">::</span><span class="identifier">generic</span><span class="special">::</span><span
            class="identifier">stream_protocol</span></code>:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">ip</span><span class="special">::</span><span class="identifier">tcp</span><span
            class="special">::</span><span class="identifier">acceptor</span> <span
            class="identifier">my_acceptor</span><span class="special">(</span><span
            class="identifier">my_io_context</span><span class="special">);</span>
<span class="special">...</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">generic</span><span
                class="special">::</span><span class="identifier">stream_protocol</span><span
                class="special">::</span><span class="identifier">socket</span> <span
                class="identifier">my_socket</span><span class="special">(</span><span
                class="identifier">my_io_context</span><span class="special">);</span>
<span class="identifier">my_acceptor</span><span class="special">.</span><span class="identifier">accept</span><span
                class="special">(</span><span class="identifier">my_socket</span><span class="special">);</span>
</pre>
    <h6>
        <a name="asio.overview.networking.other_protocols.h2"></a>
        <span><a name="asio.overview.networking.other_protocols.see_also"></a></span><a class="link"
                                                                                        href="other_protocols.html#asio.overview.networking.other_protocols.see_also">See
        Also</a>
    </h6>
    <p>
        <a class="link" href="../../reference/generic__datagram_protocol.html" title="generic::datagram_protocol"><code
                class="computeroutput"><span class="identifier">generic</span><span class="special">::</span><span
                class="identifier">datagram_protocol</span></code></a>, <a class="link"
                                                                           href="../../reference/generic__raw_protocol.html"
                                                                           title="generic::raw_protocol"><code
            class="computeroutput"><span class="identifier">generic</span><span class="special">::</span><span
            class="identifier">raw_protocol</span></code></a>, <a class="link"
                                                                  href="../../reference/generic__seq_packet_protocol.html"
                                                                  title="generic::seq_packet_protocol"><code
            class="computeroutput"><span class="identifier">generic</span><span class="special">::</span><span
            class="identifier">seq_packet_protocol</span></code></a>, <a class="link"
                                                                         href="../../reference/generic__stream_protocol.html"
                                                                         title="generic::stream_protocol"><code
            class="computeroutput"><span class="identifier">generic</span><span class="special">::</span><span
            class="identifier">stream_protocol</span></code></a>, <a class="link" href="../../reference/Protocol.html"
                                                                     title="Protocol requirements">protocol
        type requirements</a>.
    </p>
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                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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